CLIC Controls – for the CDR

1. CLIC Controls – for the CDR Mick Draper Accelerator Control group, CERN

2. CLIC Controls • Talk outline • Mea Culpa • Scope • Key points to address • Status

3. CLIC Controls – mea culpa • I really came here to grab people who had not yet produced their CDR contribution • But got landed with this talk • Since IWLC2010, in Geneva, there has been little concrete progress (at CERN) on the design on the CLIC control system: • J. Serrano has produced a final version of the “Fine-timing” section for the CDR. • There is a first draft of the CONTROLS section for the CDR. • With the exception of the description of the ACM, the CDR draft is still qualitative than quantitative • Really was meant as a draft for comments! • Waiting for the comments ! • No specific R&D has been done for a new control system

4. CLIC Controls – Scope • The “CLIC control system” will be implicated in all areas of the CLIC complex. • Will consist of several sub-systems which will take care of individual parts of the complex • Final organisation will be determined by the needs of the operations teams. • For the moment, the working assumption is that most of the complex will need only standard or ‘state of the art’ controls solutions. • The exceptions are: • The main linacs • LLRF, some instrumentation & TBA which need fs-level timing

5. CLIC Controls – Challenges • If all goes well, here we are talking about computer systems which will be deployed in 10-15 years from now. • I don’t have a crystal ball so can’t know what tomorrow’s servers will look like, so we assume: • we will see an evolution and not a revolution and that there will no radical move away from today’s architectures • We assume that we will be using the same s/w technology as today • Must not fall into the trap of specifying architecture choices too soon or they will already be out of date before they are installed (c.f. LHC Front-end systems)

6. CLIC Controls – Challenges • With the CERN accelerator complex, we have learned from many years of practical experience and so, I expect, the future CLIC Control system to based on the same principals: • Modularity • Lets us re-use components throughout the complex • 3-tier architecture • Equipment-tier – interaction with the h/w • Middle-tier – contains the business logic (middleware) • Client-tier – GUIs for operating the machines

7. CLIC Controls – Challenges • Strict limitations of heat dissipation into Main Linacs tunnel. • Force us to adopt a novel architecture • Development of the CLIC Front-End Acquisition nd Control Module (ACM) • see previous talk • Scale of the 3 TeV project • Enormous numbers of instruments to be read-out • 50 Hz cycle-time • How to handle the data rate • Need to define well what we want to keep • The LHC experiments are the experts in data reduction so if we need help we know who to ask

8. CLIC Controls – Timing Challenges • Timing (see Fine Timing section in CDR) • LLRF • Reference clock signal distribution requires 50fs jitter • Beam Instrumentation • Longitudinal profile monitors. • Clock precision of few 10s of femtoseconds • 2-beam acceleration • Needs very precise synchronisation between MB and DM • Use kickers to modify the trajectory • Required precision is about 40fs

9. CLIC Controls – Timing Solutions • Continuous Wave (CW) system • Pulsed system • Technical issues • Both systems have been tested only over several hundred metre long fibres • 25km needed for CLIC is well beyond the current state of the art • Laser coherence length • Brillouin scattering with the fibres • Limits optical power which can be transmitted (CW system) • Should build demonstrators of both CW and Pulsed systems • Who wants to get involved ??

10. CLIC Controls – ACM • LAPP (Annecy) working on prototype • See previous talk • Having seen John Osborne’s CES chapter, we can use “stub caverns” (every 878m) • Keeps electronics away from radiation • Take signals from 400+ ACM’s via fibres • Concentrate and do first processing • Next level of concentration will be at the surface buildings. • Final data concentration will be in “server farm” close to the control centre

11. CLIC Controls – Future Plans • The 2 CERN Controls groups have not yet “engaged” with the wider CLIC community; • There is contact between CERN and CRNS for the ACM • Need to start a more formal collaboration • Make sure that h/w developments are compatible • Or at least minimize the incompatibilities • First contacts between the CERN Timing team and DESY • DESY are the experts on the CW approach to fs timing • There is a Fieldbus working group at CERN • Mostly dominated by the CERN experiments • Need to establish CLIC’s requirements as part of this group • Decide how/if CERN’s “White Rabbit” initiative can be integrated • We need to create an active CLIC Controls Collaboration to discuss: • Architecture issues • potential showstoppers • How best to harness existing efforts and expertise !!

12. http://project-clic-cdr.web.cern.ch/project-CLIC-CDR/

13. CLIC Controls

15. CLIC Controls – Scope • The proposed 3TeV CLIC is a very large accelerator complex; consisting of: • Sources • Injectors • Damping and Combiner rings • Transfer lines • Main Beam (MB) and Drive Beam (DB) linacs • Experimental area(s)